Means for the production of long continuous electric arcs.



O. SOHUNHERR &: J. flEsSBERGER. MEANS FOR THE PRODUCTION OF LONG CONTINUOUS ELECTRIC ARCS.

APPLICATION FILED MAY 18, 1910. I 1, 1 1 5,249. Patented Oct. 27, 1914.

2 SHEETS-#33111 1.

Fig. 2. F1 3 2.

F L x A L L -r r- L P I l J l K T l 0. sOHD HERR & J. HESSBERGBR MEANS FOB THE PRODUCTION LQNG CONTINUOUS ELECTRIC ARCS. APPLICATION PILED HAY 18, 1910.

I 1,115,249. Patented Oct; 27, 1914.

I 2 SHEETSSHEBT 2.

wi/tmwaeo 3 W00 m/fom nurrnn sra rnsraranr caries.

OTTO SCHNHERR, F CHRISTIANIA, AND JOI-IANI-TES HESSBEBGER, 0F CHRISTIAN SAND, NORWAY, ASSIGNORS, IBY MESNE ASSIGI-TIYIEKTS, f0 NORSK HYDRO-ELEK- TRISK- KVHLSTOFAKTIESELSKAB, OF GHRISIIANIA, NORNAY.

MEANS FOR THE PRGDUCTION CF LONG CCYNTINUOUS ELECTRIC ARCS.

To all whom it may concern:

Be it known that we, Or'ro Sciionnnnn, Phi D., chemist, and JoHANNEs Hnssnnnonn, electrician, subjects, respectively, of the King of Saxony andthe King of Prussia,

residing, respectively, at Christiania and Christiansand, Norway, have invented new and useful Improvements in and Means for the Production of Long Continuous Electric Arcs, of which the following is a specification.

In the-specification of Letters Patent No. 930238 we have described the. production of long stable electric arcs by bausing an arc to spring from an insulated electrode con nected with one pole of a source of-electricity and situated at, or toward,'one end of a long tube, or passage, the,tube, or passage, itself being either connected with the other pole of the source of electricity, or contain ing at, or toward, the other end thereof,

second electrode connected with the other pole of the source of electricity, while at the same time a current of air, or other gas, or gases, is passed through the tube, or passage,,with suclrvelocity that a long and steadily burning electric arc is produced and maintained within the said tube, or passage. The said specification discloses, for the time, a new principle, namely surrounding a long electric arc with alayer of non-conducting fluid and maintaining this layer of fiuid in sucha condition that it is easier for the arc to continue. in the position in which it is burning than for it to spring through the layer of surrounding fluid. In order to bring about this condition, it necessary that the layer of gas, (which we will hereinafter, for brevity, referto as air, although other gas, under which term. we include a gaseous mixture, may be used in carrying out this invention) should not be allowed to become so hot that it is capable of conducting, electricity, or at all events that it should not reach this high ten'iperature until it arrives at a point in the tube, 'or passage (which we will hereinafter, for brevity, refer to as the lube), where it is desired that the arc should pass through the layer to the second electrodeor its equivalent. A particular method of carrying out the principle set forth consists, as described in the aforesaid specification, in passingv a current of air in one direction through the tube, in

'whichthe arc is produced, commencing at a point either below, or at a shortdistance Specification of Letters Patent.

Patented oer. 2?, ram.

Application filed Eay 18, 1910. Serial No. 562,097.

above, the insulated electrode. It is also preferable, according to the said specification, that the air should be passed into the tube with a tangential, orrotatory,anotion. The specification of Letters Patent No.

976,002 describes the production of stable electric arcs by means of two tubes, each provided with an insulated electrode and leadlng into a common space. Air is blown past each electrode into the respective tube and is led away from the common space, while the arcs produced may join in the common space and form one continuous are. In Fig. 3'of the drawings accompanying the last-named specification the two tubes air passing through the tubeas described in the said specification, the arccan also be produced and maintained with certain advantages if the air be made to pass through the tube or through different portions of the tube in different directions lengthwise of the tube at one and the same time as hereinafter explained. For instance the air can be passed along the wall insideth'e tube in one direction and then back again in the reverse direction immediately surrounding the arc, so that it passes through the said tube or through different portions thereof, side by side, in different directions lengthwiseof the said tube at one and the same time, or the air can be caused to pass in two opposite directions along different portions of the arc, being intrmluced for instance into the tuhc at a point between lhe two ends thereof, and the gases being removed from the lube at, or near, each of the two ends thereof sin'iultaueously, preferably being withdrawn through each electrode, or through the parts ofthe apparatus which act as elecli'mles, or these variations can be combined so that air is introduced into the tube at each of the two ends thereof and passes along Lheinterior wall toward the mid part and, then reverses its course as to pass back along the are toward 621Cl1 "0f the twoendS-nf the tube again.

When carrying out this invention we pre-. fer to impart to the air, or to part of the air, entering the tube a tangential, or rotatory, motion, for instance such as is described in the aforesaid specification of Letters Pat- 'ent No. 930,238, and it is also generally T taining the electric arc with a second tube and to pass the air through the space between the two tubes before allowing it to enter the inner tube, so that in this way the temperature of the inner tube is lowered and the air becomes preheated before entering the inner tube and consequently a higher temperature of the arc is admissible within the inner tubethan would be the case if no Such preheating took place. When,,according to this invention, the air passes along the interior wall of the tube and then back again immediatelysurrounding the are, a further advantage is atta1ned,because heat is able to pass dlrectly from vthe air imme- 'diately surrounding the arc to that which is moving in the opposite direction along the interior wall of the tube, and the transference of heat is' greater because there is no intermediate wall through which the heat has to pass and since the hottest air does not come into contact with the wall of the tube a much higher temperature of the arc can be employed within the tube than would be the case if the temperature of the are bad to be restricted to prevent the material of which the tube is made from being injured.

When the air is led into the tube at one end only and the gases are removed at the same end, the tube can be cone-shaped the entrance and exit being at the larger end of the cone.

If desired, instead of introducing the whole supply of air into the tube in the manner tereinbefore described, it 'can be introduced partly in such manner and partly in any oth r suitable way, for instance as described n the specification of the aforesaid Letters patent No. 930,238.

The electrodes employed in carrying out the process according to this invention can be of various shapes. For instance they can berod-shaped, as described in the aforesaid specification of Letters Patent No. 930,238, or'they can be formed like a ring, and the end of the arc can continually move around the ring.

We give the following ways as examples of how this invention can be performed in practice, referring to the accompanying drawings, but the invention is not limited to these examples. 7

In the drawings, each of the Figs. 1 to 4,- inclusive represents vertical seetions of apparatus suitable for use according to this invention, showing how the electric arc can be, produced and how the gas is caused to pass in the desired direction or directions.

In the arrangement shown in Fig. 1, two tubes are employed, namely an upper one K, of inverted funnel shape, partly entering a lower tube Rv so that there is a small ringshaped opening r between them and through this opening the air is passed with a suitable velocity into the lower tube R, the said air passing down the interior ofthe wall thereof toward the electrode'P which is situated at the lower end of the said tube R, and then taking a course in the opposite direction, as indicated by the arrows, and passing away through the upper tube K. When an electric arc is formed between the electrode P and the upper tube K, or a special electrode situated in the said tube K (for instance by momentarily short circuiting these two parts), the are produced burns quietly in the lower tube R starting from the electrode]? and ending either on the upper tube K, or on the special electrode situated in the said tube K. We prefer to introduce the air into the lower tubeR so that the said air has a tangential or rotatory, motion, and for this purpose an apparatus such as that illustrated in Fig. 2 can be employed. In this figure, E isa metal ring situated in the upper part of the lower tube R, the said ring E having tangential openings in it so that the air passes into the tube R with a rotatory motion, and for the greater part downward along the interior wall of the tube R toward the electrode P, then takes an upward course nearer the axis of the tube R, and finally the gases pass away through the upper tube As shown in the figure, the said electrode P and the lower tube R may be electrically connected together and be insulated from the other parts of the apparatus. The electric arc can be started by short-circuiting the upper and lower tubes R and K, the one end of the are being driven down by the air current and terminating on the said electrode P, which is preferably cooled, for

instance by means of water. As shown in this figure, the lower tube R,v can be surrounded by the second tube and the air can be passed, through the pipe 6, upward between these two tubes before entering the inner tube R through the aforesaid tangentially perforated ring E. The other end of the arc can besituated on the upper tube this electrode and the electrode P. In-

stead of all the air passing through the.

aforesaid ring E down the lower tube, some of it may be passed up the upper tube K without entering the lower tube R, .and the proportion of air which follows this course \will depend upon the relative sizes of the tubes K and B. This is the case with the arrangement Fig. 2. The portion of the air passing directly through the upper tube K mixes with the heated gases leaving the lower tube R and tends to cool them down 'quickly, and this is of advantage when the electric arcs are used for carrying out endothermic reactions in gases, for 11181331166 for the production of nitric oxid. Of course the gases can be further subjected toa cooling process by using special 'means for cool-' ing the upper tube K, for instance it can be surrounded by a water-jacket after the manner of a Liebigs condenser.

Fig. 3 illustrates the use of a cone shaped lower tube R which is insulated from the rest of the apparatus, the air passing in through the opening 7' between the tubes K and K into the lower tube, down the interior inclined wall thereof and then upward surrounding the aXis. If desired, air can also be introduced at the lower end of the said lower tube R as illustrated by the arrow. \Vhen such an apparatus is used there-is a tendency for the end of the arc to describe a circular path around the inner wall ofthe cone-shaped tube R.

Fig. 4c illustrates an arrangement in-which air is introduced at each of the two ends of the tube R, passing along the inner wall thereof, then reversing its course so as to pass back along the arc, the gases finally leaving the tube through the two insulated electrodes P, P, and passing out by the passages K, K The electrodes may, if desired, be cooled by means ofw'atei'-ja :kets. A ring T may,'if desired, be situated, as shown, in the tube R to assist in directing the courseof the air which enters at any convenient number of openings (indicated at E E with sufficient velocity to follow the courses indicated by the arrows. The are can be formed by causing a short-circuit, either between the two electrodes, or between each electrode and the tube It. If desired, however, one of the electrodes may be electrically connected to the tube R, while the other electrode is insulated therefrom, in which case the arc can be started by short-circuiting this second electrode withthe tube R. 1

In all the figures L represents insulating material.

Now what we claim is 1. The process of producing. a long stable electric arc in. a tube or passage provided with an insulated electrode by causing a gas to pass throu h the arc tube in different directions lengt wise of the said tube at-o'ne and the same time.

2. The process of producing a long stable electric arc in a tube or'passage provided with an insulated electrode by causlng a gas to pass into the arc tube about at one or more than one lace at or near the mid part of the length of the said tube or passage and to pass out from the said tube or passage near each of theelectrodes which are situated at or near each end of the tube or passage substantially as hereinbefore explained.

3. The process of producing a long stable electric arc in a tube or passage provided with an insulated electrode by causing-a gas to pass into the tube or passage at each of the two ends thereof and then to pass along the wall toward the mid part and then to reverse this course so as to pass back along the arc toward each of the two ends of the tube or passage again substantially as herein-- before explained.

41-. The process of producing a long stable electric arc in a tube or passage provided with an insulated electrode by causing a gas to pass into the tube at each of-the two ends thereof and then to pass along the wall toward the mid part and then to reverse this course .so as to pass back along the arc toward each of the two ends of the tube again and causing the air to-leave the tube through the electrode while cooling the said electrode or outlet, substantially as hereinbefore explained.

5. An apparatus of the kind described comprising 'a tube with a hollow electrode situated at or near each'end thereof, means for introducing gas at or near each end thereof, and means for causing thegas enter-, ing at each end to travel toward the mid part of the tube and then to reverse its course so that the gas which enters the tube at one end leaves the tube substantially through the electrode situated at the same end of the tube at which the gas enters the tube. I

In testimony whereof we have hereunto set our hands in the presence of two subscribing witnesses. OTTO SCHONHERR.

J .O'HANNES HESSBERGER.

Witnesses to the signature of Otto Schonherr:

ERNEST L. IVES, W. W. SCHMIDT..

Witnesses to the signature of Johannes Hessberger:

A. W. ABEL, SIGR 

